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The model test is an effective means to verify the mechanical performance of the bridge structure and to ensure the structural safety. The accuracy of design and manufacture is the key of model test.For a arch ridge with curved beam and skewed arch, the model test based on the similarity theory is analysized in detail including selecting materials, designing the size of section and calculating the geometrical parameters and so on, and the simulation reults between model and prototype are evaluated.Meanwhile some key technologies and valuable matters for design of aerodynamic model are presented,which provides an important reference value for model design of bridge structures.

Studying the deformation and fracture properties of soft materials can not only provide insight into the physical mechanisms underlying their superior properties and functions but also benefit the design and fabrication of rubberlike materials. In this paper, an application of the experimental digital moire method to determine the damage zone around crack tip for rubberlike material is presented. The measurement principles and the basic procedures of the method are explained in detail. The in-plane defomation distributions of crack tip fields under Mode I fracture condition are measured. In addition, the deformation of crack tip fields in the damage zones is also analyzed using the sector division mode. Finally, an analysis of the damage zone is proposed to describe crack-tip fields in rubber-like materials with large deformation.

A new constitutive model which is modified from Gao’s constitutive model has been introduced to analyze the finite deformation of a circular membrane with an embedded rigid inclusion under uniform pressure. Based on the basic controlling equations, the constitutive parameters and the dimension of the rigid inclusion have been discussed to demonstrate the influences on the membrane stresses.

Following the modified Gurson model in meso-mechanics, the models with spherical holes are established by the assumption which the matrix meets the two-parameter elliptic yield condition. The macroscopic stress expression which contains micro structure parameters and the material equation of yield surface are given by the upper bound theorem of plastic limit analysis. The parameters of the matrix material and damage(porosity) which impact on macroscopic yield surface equation are discussed. These works provide theory foundations for material damage and design.

One kind of multi-void three-dimensional microstructure models based on homogenization method is constructed. Based on multi-void microstructure, the mathematical models for the topological structural optimization which takes maximizing the total potential energy as the objective function is constructed, then the Kuhn-Tucker optimality condition of the update method about the designs variable based on the porous microstructure can be gotten when optimization iterates. Finally, in explaining the employed algorithm an example is provided.

At present the study on the application of the topology optimum design in scraper conveyor is still under development. In this paper the topology optimization based on the homogenization method is applied to the design of the baffle on the scraper conveyer, which can provide a valuable conceptual design scheme for the selection of the baffle pattern. In conjunction with the homogenization theory and Finite Element Method (FEA), the mathematical models for designing the baffle by the minimizing mean compliance are developed in this paper. By applying the topology optimum design to the baffle, the topology optimization based on the homogenization method is proved to be reliable and practical at the conceptual design stage of baffle.

The volume fraction of inclusions is one of the most critical parameters of polymer composites, which affects or even decides the mechanical behaviour of the materials. A procedure to calculate the volume fractions of inclusions of any size and shape distributions in polymer composites is introduced. It combines the capabilities of a digital processing technique to obtain configuration parameters of inclusions and of a statistical analysis which determines their volume fractions.The measurement principles and the basic procedures of the method are explained in detail. The procedure has been validated on simple shapes. The subsequent analysis is carried out using the method and is shown to be stable in some cases.

At present the study on the application of the topology optimum design in scraper conveyor is still under development. In this paper the topology optimization based on the Solid Isotropic Material Penalization (SIMP) is applied to the design of the middle pan, which can provide a valuable conceptual design scheme for the selection of the middle pan pattern. In conjunction with the homogenization theory and Finite Element Method (FEA), the mathematical models for designing the middle pan by maximizing the rigidity are developed in this paper. By applying the topology optimum design to the middle pan, the topology optimization based on the SIMP method is proved to be reliable and practical at the conceptual design stage of middle pan.

With the increasing development of polymeric materials, it becomes important for research on mechanical properties of polymeric materials under large deformation conditions. To know displacement distributions in the polymeric structures could help us to better understand the deformation characteristics of polymeric structures in fracture analysis. In this paper, an experimental digital moiré method for the in-plane deformation measurement in a sample of transparent polymeric material, which is a non-contact method for full-field, large deformation and real-time measurement, is presented. The measurement principles and the basic procedures of the method are explained in detail. In order to demonstrate this method, a cross grating is generated and put into a transparent polymeric specimen. The subsequent fringe and displacement analysis is carried out using the method developed by the authors.

Within the last 30 years, a number of methods have been proposed such as boundary-based shape optimization, homogenization-based method, evolutionary structural optimization etc [1]. Design optimization is used to produce a design that possesses some optimal character, such as minimum weight. However, these optimization capabilities are basically used to improve the design of structures or parts in the detailed design process. In the beginning of conceptual design process, another method of optimization what is called topology optimization is necessary. Based on the homogenization method, which is introduced by Bendsoe and Kikuchi [2] in 1998, topology optimization has become an important and well-recognized sub-area of structure optimization. This theory has been extended and applied to several of kinds of problems such as static problems and mode problems [3].